1. Field of the Invention
The present invention relates to a hot water supply and heating system associated with a heat pump and a method for controlling the same.
2. Description of the Related Art
A hot water supply and heating apparatus associated with a heat pump is an apparatus which is combined with a heat pump cycle and a hot water circulation unit and performs heat-exchange between water and refrigerant discharged from a compressor which constitutes a heat pump refrigerant circuit to perform a hot water supply and a floor heating.
In a conventional system, a pipe for water flowing along a closed cycle for heating is separated from that for supplying hot water, and heat exchange is performed at each different spot of the pipe on the outlet side of the compressor of the heat pump refrigerant circuit. That is, in the conventional system, a water-refrigerant heat exchanger for heating and a water-refrigerant heat exchanger for hot water supply are separate.
In the conventional system, water supplied for hot water supply performs heat-exchange with the refrigerant, while passing through the water-refrigerant heat exchanger for hot water supply, and is then directly discharged.
The hot water supply and heating apparatus associated with the heat pump having the structure as described thus has the following problems.
Firstly, when frost is generated on a surface of an evaporator which constitutes the heat pump refrigerant circuit and a defrosting operation is thus needed, heating and hot water supply functions must stop completely until the defrosting operation is finished. During the defrosting operation, the hot water cannot thus be supplied and indoor temperature is also reduced. If a heating operation is also performed while the defrosting operation is performed, heat is transferred from the water-refrigerant heat exchanger to the refrigerant, so a temperature of the circulating water drops to cause a drop in a temperature of an indoor floor.
Secondly, even though the hot water supply and heating are performed again after the defrosting operation is finished, it takes some time for the heating circuit reaches a normal level and the hot water supplied reaches a set temperature.
Thirdly, the water-refrigerant heat exchanger for heating and the water-refrigerant heat exchanger for hot water supply are separate, so an installation process is complicated and a manufacturing cost is increased.